Brake mechanism.



F. HORN.

BRAKE MECHANISM.

APPLICATION FILED FEB. 5, 1911.

1,147,507. Patented July 20, 1915.

2 SHEETS-SHEET I.

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COLUMRIA PLANOGRAPH CO.,\VASHINGTON, u. c.

F. HORN.

BRAKE MECHANISM.

APPLICATION FILED FEB. 6. 1911.

' 1,147,507. I Patented July 20, 1915.

' 2 SHEETS-SHEET 2.

COLUMBIA PLANOGRAPH c0., WASHINGTON, n. c

FRANK norm, or ooLuMBUs, onro.

BRAKE MECI-IAEN' Specificationof Letters Patent. PatentedJ-fily 20,1915.

,Application filed February 6, 1911. i S eria;l1 Io. 606,796.

To all whomit may concern n:

Be itknown that I, FRANK HORN, a citizen of the United States,residingat Colum bus, in the county of Franklin and State of Ohio, haveinvented certain new and useful Improvements in Brake Mechanism, ofwhich the following isa specification.

The present invention relates to certain novel and useful improvementsin brake mechanism and has particular application to automatic adjustingmeans for taking up the slack of the brakes ofrailway trains, cars andthe like. I

In carrying out my invention, it is purpose to provide an automaticslack ad juster, adapted to eliminate the excess of slack in the brakeconnection of cars, whereby a practicallyv uniform pressure of the brakeshoes upon the car wheels, is attained, resulting fromthe vpiston travelbeing maintained constant at the brake cylinder. This piston travel isregulatedby the amount'of slackv at the brakes, and bycertain featuresof construction in taking up such slack through lengthening theconnection between the truck levers, the correct alinement of the leversis maintained, and the maximum efficiency of the brakes is at all timesrendered automatically available.

Stilla'further object of my invention is to provide an automatic slackadjuster em bracing the desired features of simplicity, durability and:strength, ,and one wherein the existing elements .of well known brakestructures, may be utilized :to a great degree.

Another object of my invention is to .provide mechanism of theycharacter described, which is positiveand eflicient-in action and whichmay be constructed to take up slack at any desired amount of pistontravel, by regulating the dimensions of the teethon the rack of thebottom connection,,andupon therack shoes respectively.

I also .aim to providea slack adjuster which will operate with eitherhand brakes or air brakes, and which is re'adilyaccessible for thepurpose of renewingthe brake shoes, or performing other work.

While I have herein shownand described my invention as .applied to oneparticular type of brake .mechanism,.I wish it to be understood that Ido not limit myself ton-the employment of my invention in connectionwith this particular type of mechanism, as

it, may :be used with other forms of brake devlces without departingfrom the inven= tion, or exceedingthe scope of the appended claims.

My invention consists in the construction, combination and arrangementof parts set forth in and falling within scope of the ap-' pendedclaims. I In the accompanying drawingsFigure 1 s a topplan view of aportion of a car truck and showing my invention employed in connectionwith the brake mechanism, Fig. 2 is a view in side elevationof a cartruckhaving "my automatic ,slack adjuster applied thereto, thebolster ofthe truck being shown in section, Fig. 3 is a top plan view of thebottom connecting .rod showing the rack formed in one end thereof, Fig.4 is a side View of'the same, Fig.5 .lsya face view of one of the rackshoes and showing the serrated surface thereof, Fig. 6 is a longitudinalsectional view upon the line 6+6 of Fig. 5, Fig. 7 is a viewin sideelevation of the tension springwhich bearsagai-nst the upper rack shoe,Fig. 8 is a. detail view showing the ,pin carried by the live lever andadapted to support the bottom rack shoes, Fig. 9 is a detail view of thepin for retaining the tension spring shown in Fig. 7 in positiomand,Fig. 10is atop plan view of the spring shown for maintaining the shoe inconnection with the rack.

Referring nowtojthe accompanying drawings -'i-ndetail,A designates thetruck as an entirety, and the numerals 1 designate the axles, while thewheels are shown at 2. The central truck bolster is indicated by the numeral' 3 and the brake beams are shown at at, saidbeams carrying thestruts 5, to which in turn are connected the tension members 6, leadingto the brake heads 7, there being as usual one head for each wheel, andeach head is providedwith a brake shoe 8. "These brake headsare carriedby brake hangers 7 pivotally mounted as at' 7 to brake hanger brackets7, which arein turn supported in any well known manner by. the bolster3. The push or pull rod 9 leading from the brake cylinder is connectedas at .10 to the .live lever 11, moving within the lever guide. 12, andpivoted asat' to the strut 5 of the brake beam. 7 Thenumeral 15 is ashort connecting-link of a 'well known mechanism for keeping thebrakeshoes out of engagement with the.

wheels when the brakes are in full released position which connects thestrut 5 with the spring rod 16 leading toward the brake beam of theother set of truck wheels, said spring rod being connected with theshort link 17, which in turn connects with the strut 5. The dead lever20 is pivoted at 19 to the strut 5, said strut 5 being also secured tothe brake beam as at 21, and the dead lever at its upper end is adaptedto be pivoted as at 22 to the fulcrum-bar 28, the lever guide of thelive lever and the fulcrum bar of the dead lever both being connectedwith the truck bolster.

The numeral 24 designates the connector or bottom connection rod, oneend of which is offset and has its upper and lower faces serrated instaggered relation with each other as at 25 to form rack surfaces, thisend being slotted as at 26 to permit the passage therethrough of thelower end of the live lever 11, so that the end of the bottom connectionrod is carried in loose engagement with thelower end of the live lever.

At 28 is shown the lower rack shoe, shown in detail in Figs. 5 and 6,having the surface which contacts with the rack of the rod, serrated ortoothed as at 29 to correspond with the serrations 25 on the connectionrod 241-, and having its outer face plain and formed with a flange 30,which face is adapted to contact with the pin 31, shown in detail inFig. 8, passing transversely through the lower end of the live lever,said pin having apertures 32 therein for the reception of cotter pins.Instead of employing a pin with a boss or head, such as is commonly usedin practice, and which head would be liable to come in contact with thelower shoe, and thereby dislodge the same or otherwise interfere withits operation, I prefer to employ a pin such as is shown, comprising ashank or body having the openings therein for the reception of cotterpins, the body of the pin outside the openings forming a smooth firmbearing for the lower rack shoe. This lower rack shoe is also providedwith an opening or slot 34: to permit the passage of the end of the livelever, and such opening is central as regards the width of the shoe, butis preferably slightly offset as to length, to provide more metal at theportion through which the force is transmitted. The upper rack shoeshown at 33 is identical in construction with the lower rack shoe, sothat the shoes may be used interchangeably, thereby obviating thepossibility of an/unskilled workman making a mistake in the applicationof the shoe. This slot is enough longer than the lever is wide, to admitof slight play and allow such angularity of lever as may be necessary.In fact, I find it advisable to offset the slots in the rack shoeslongitudinally thereof also for the purpose of assisting in maintainingthe lever mechanism in proper position of alinement.

The flanges which are in the nature of lateral wings or extensions ofthe shoes, are adapted to aid the operation of removing the shoes fromthe rack, when it is desired to return the rack shoes to initialpositions. Said flanges form projections which may be grasped by theoperator in one manner of making the change, or the flanges may formbearings for a suitable tool which may be employed in prying or forcingthe rack shoes apart.

The upper shoe which has its serrated face in engagement with the upperrack, is resiliently held in position through the medium of a tensionmember in the nature of a coiled spring 35, shown in detail in Figs. 7and 10, where it will be noted that such spring is substantially oblong,thereby forming a bearing surface for contact with the shoe and with theretaining pin 86, which passes through the live lever and holds thespring in place. This pin is shown in detail in Fig. 9 and has two holes37 for the reception of cotter pins, the end of said pin 36 beingbeveled or pointed as at 38, so that when the spring is free, the pinmay find ready entrance to the hole 39 in the lever and at the same timesubject the spring to slight tension.

The opposite end of the connection rod 24 from that carrying the rack,is formed with a bifurcated end portion 40 having ap ertures 41 therein,to which may be pinned 1 the lower end of the dead lever. The live leverhas connected thereto as at 42, one end of the release spring 43, theopposite end of said spring being fast to the bolster as at t The aboveis a detailed description of my slack absorbing mechanism shown appliedto a well known type of brake mechanism, it being understood that it isequally as applicable to various other brake mechanisms now in generaluse.

The operation of my device is as follows: A pull upon the rod 9 from theair cylinder (not shown) will cause the live lever 11 to move forwardabout the serrated portion of the connection rod 24. as a fulcrum point.This forward movement carries the brake shoes forward into brakingengagement with the periphery of the wheels 2. When the brake shoesadjacent the live lever have come into contact with the correspondingwheel, the fulcrum point of the live lever is changed to the pivot point13 and the connection rod 24- is forced rearwardly by the action of thelower end of the lever bearing upon one wall of the slot 34: in thelower rack shoe 29, it being understood that this rack shoe is held ininterlocking relation with the lower serrated surface 25 of the ofisetend of the connection rod 24. This rearward movement of the connectionrod causes the dead lever 20 to pivot about its fulcrum point 22,thereby forcing the oploosev engagement with the ra'ck'portions oftheconnection rod through the medium of the spring'35 and, asalready'stated,-under normal conditions the dead lever is actuated bythe action of the live lever bearing upon the lower rack shoe while thesame is thus held i-n'its engagement with the lowerra'ck surface.However, should the brake shoes have become worn, or should any of theother portionsof the mechanism have-be come worn so ithatan amount "oftravel ofthe live lever in excess of What is normal is required togivethe desired braking effect, this excess amount of travel causes the livelever to bear against one of" the short walls of the slot 34 in theupper rack shoe and, since this shoeis resiliently held in positionbymeans of the spring 35, it will be made to climb the correspondingserrations upon the upper surface of the offset end ofthe connection rod24:. When this excess'movement has reached a predetermined amount, thelongitudinal movement of the upper rack shoe "will be enoughto cause ittomove the distance of one tooth, in which position it will again beresiliently held by the spring 35. When this longitudinal "movement ofthe upper rack shoe has taken place, return movement of'the live lever11' pivoting about the point 13 will cause the lower end of this leverto bear upon :one of the short walls of the slot "34 in the lower rackshoe and will cause it also to' move the distance of one tooth. In thismanner, when there has resulted an excess amount of slack, it'will beautomatically taken up by the mechanism of my invention asabovedescribed. I'have resorted to the use of "the spring 35 for resilientlyholding the rack shoe 'in position, but I wish itto be understood thatthe use of this spring is not-absolutely essential as the parts will.properly perform their function by the action of gravity alone, althoughtheir operation is made more'posi tiveby the use of this spring. 7 a

What I claim, is g 1. In an automatic slack adjuster for V brakemechanism, the combination with the brake mechanism including the brakeshoes and actuating levers t-herefor',and"mecha nism' extending between-levers including a rack-and a plurality ofshoesadapted to move alongsaid rack to take'up slack, said shoes being capable of independentvertical and horizontal movement with reference to the levers.

2. In an automatic slack adjuster, the combination with brake mechanism,including a plurality of brake shoes and actuating levers therefor, of aconnector extending b'e- As stated, the rack shoes are held incomparatively.

tween saidlevers, and means for varying the distance between the leversin contact with said connector,- said "means consisting of a rackformed-on one end ofsaid connector, and rack shoes adapted to engagesaid rack; said rack and-rack shoes being carried 1n loose engagementupon one of said' levers, said rack 'and rack shoesibelng capable ofindependent vertical andhorizontal movement with reference to saidlever. v

3. In anautomatic slack adjuster,"the

combination with brake mechanism, including a plurality of brake shoesand actuating levers therefor, a connector extending; be-

tween said levers'havin onefend formed with arack loosely supportedfrom-one of said levers, a plurality of rack shoes identical instructure, adapted to engage sa'id rack and be carried on either sidethereof upon said lever, said rack shoes being adapted upon themovementof said lever to travel along said rack, thereby to change relativeposition of said rackwith reference to said lever, and means fortensioningsaid rack shoes, said means consisting of -a tension memberbearing on'the back "facefof one of said rack shoes and a tapered yp'inadapted 'to stop movement of said tension member.

In an automatic slack adjuster, the combination withhrake "mechanismincluding the brake shoes and live and dead levers therefor, .ofaconnector having one end connectedto the dead lever and "its oppositeend formed 'Withwa rack slotted to permit the passage therethrough ofthe live lever, slotted rack shoes adaptedto "engage with said rack andfto'be operated by the movement of the live lever to 'varythelength ofthe connectonre'lative' to the live and dead levers andther eby take upslack, saidrack and rack shoes being capablexofa lim'ited hori- 1 zontalandvertical movement with reference v to the "live lever. i

5. Inxan automatic slack adjuster,- the combination with brakemechanism, includi'ng'atherbrake shoes and live and dead leverstherefor, and means whereby the live" lever is caused-to assume "a fullrelease position when brakes are not applied, said means, through themedium-of said levers preventingbr'ake shoe contact with the peripheryof the wheels when the brakes are'released, a bottom connector connectedtothe dead lever and having a rack portion loosely suspended from thelive lever, upper and lower shoes adapted to, slide upon said rack, apincarrie'd by the live-lever and adapted to form a restricted slidingbearing for the lower rack, shoeyaf" tension "spring abovethe upper rackshoe and ten'sioned against said-lever and-a tapered adapted to "holdsaid spring' in position,

" T6,;In an automatic slackadjuster, the

combination 'wi-th' "the brake mechanism-ineluding thebrake shoes andoperating levers therefor, of a connector fastened to one of said leversand having a slotted rack at its opposite end whereby it is held inloose engagement with the opposite lever, rack shoes carried by saidlever and loosely engaging said rack and adapted to be actuated by thesaid lever upon the application of the brake to move along said rack andthereby vary the relative position of said levers associatedv with saidconnector, means for assuring engagement of said rack shoes with saidrack, said means consisting of a plurality of pins and a tension member,one of said pins being tapered and said rack shoes being provided withflanged portions to facilitate releasing said rack shoes from engagementwith said rack when so desired.

7. In a brake mechanism, the combination of a plurality of brake leversand a connector therefor, said brake levers being adapted to actuateeach other when bra-king force is applied, through the medium of saidconnector, said connector being provided with a rack and rack shoes atone of its extremities, said rack and rack shoes being carried in looseengagement on one of said levers and adapted when actuated by said leverto vary the length of said connector, said rack and rack shoes beingcapableof independent lateral and longitudinal action with reference tosaid lever.

8. In a b 'ake mechanism, the combination of the brake shoes and leverstherefor, a connector between said levers formed with a rack at one end,said rack being carried in loose engagement on one of said levers, aplurality of rack shoes adapted to engage said rack, being carried inloose engagement on said lever on opposite sides of said rack, said rackshoes being adapted when actuated by saidlever to travel along said rackto vary the distance between the levers directly associated with saidconnector, said rack shoes being identical in structure and said rack soarranged that said shoes when fully engaged with said rack, said leverbeing in full release position, will be out of alinement with referenceto each other.

7 9. In a brake mechanism the combination of a plurality of brake shoesand actuating levers therefor, a connector between said levers, saidconnector having one end pivotally connected to its lever, the remainingend being slotted, the opposite edges of said slotted portion. beingserrated to form a rack, said slotted end being carried in looseengagement on its lever, a plurality of rack shoes being adapted toengage said rack, said rack shoes being carried in loose engagement onsaid lever on either side of said rack, said rack shoes being adapted,when actuated by said lever, to travel along said rack to vary thedistance between said levers, said rack shoes being capable ofindependent longitudinal movement as regards said lever,

said rack shoes being provided with flanged portions to facilitate theirdisengagement from said rack.

10. In a brake mechanism, the combination of a plurality of actuatinglevers and a connector therefor, said connector being formed with a rackon one end, a plurality of rack shoes adapted to engage said rack, saidrack and eachof said rack shoes being carried in loose engagement on oneof said levers and capable of independent transverse and longitudinalmovement with reference to said lever.

11. In a brake mechanism, the combination ofa plurality of brake shoesand actuating levers therefor, a connector between said levers, saidconnector formed with a slotted end having two opposite edges serratedto form a rack, said rack being carried in loose engagement on one ofsaid levers, a plurality of rack shoes adapted to engage said rackcarried on either side of said rack upon said lever, said rack shoesbeing adapted to travel along said rack when actuated by said lever,said rack and rack shoes being capable of independent lateral andlongitudinal motion with reference to said lever, a tension member beingadapted to maintain contact between said rack shoes and said rack, beingcarried on said lever, means for retaining said tension member, rack andrack shoes upon said lever.

12. In a brake mechanism, the combination of a plurality of brake shoesand act uating levers therefor, a member adapted to connect said levers,said member being formed with one end slotted to admit passage of one ofsaid levers therethrough, said slotted end portion having its oppositeedges serrated to form a rack, rack shoes adapted to engage either faceof said rack, said rack shoes being carried in lateral and longitudh nalloose engagement upon said lever, and means for retaining said rack andrack shoes upon said lever, said means being also adapted to assurecontact of said rack shoes with said rack.

13. In a brake mechanism, the combination of a plurality of brake shoesand actuating levers therefor, a connector between said levers, saidconnector having one end slotted to permit passage of the levertherethrough, said bifurcation having its two opposite edges serrated toform a rack, two rack shoes,'identical in structure, adapted to engagesaid raclg said rack being carried in loose engagement upon said lever,said rack shoes being carried in loose engagement on either side of saidrack upon said lever, said rack shoes being adapted when actuated bysaid lever, to travel along said rack to vary the length of saidconnector between said levers, said actuating lever being provided withmeans whereby when braking force is withdrawn, said lever is caused toassume its tensionvmember and said pins being adapted to assurecontinual contact -of said rack shoes withsa-id rack and to retain saidrack and rack shoes in loose engagement with vsaidalever said rack shoesbeing-providedwith flanges to. facilitate their disengagement from therack when one of said pins is withdrawn or to afford means whereby saidtension member may be compressed to admit of such disengagement of therack shoes and rack.

14-. In a brake mechanism, the combina tion of a plurality of brakeshoes and levers therefor, a connector for said levers, .said connectorbeing pivoted at one end to its lever and having its opposite endslotted and carried in loose engagement on its lever, op-

posite edges of said slotted portion being serrated to form a rack, rackshoes adapted to engage said rackand be carried in loose engagement oneither side of said rack by said lever, means for assuring contact ofsaid rack shoes with said rack and for retaining said rack shoes andrack upon said lever, said lever being the actuator whereby the rackshoes may be caused to travel along the rack to vary the distancebetween the levers at opposite ends of the connector, said actuatinglever being provided with a tension member, said tension member assuringsaid lever to assume its normal position when the brake is released,said rack shoes being capable of independent movement with reference tosaid lever and rack.

15. In a brake mechanism, the combination of a plurality of brake shoesand levers therefor, a connector for said levers, said connector havingone end pivoted to its lever and its opposite end slotted and carried inloose engagement on its lever, opposite edges of said slotted portionbeing serrated to form a rack, a pluralitv of rack shoes adapted toengage with said rack, carried in loose engagement on either side ofsaid rack upon said lever and capable of being actuated thereby, meansfor assuring said rack shoes in contact with the rack, said rack shoesbeing provided with flanges or projections to facilitate their beingdisengaged from the rack when so desired.

16. In a brake mechanism, the combination of a plurality of brake shoesand levers therefor, a connector. said connector being pivoted at oneend to its lever and slotted at its opposite end, said slotted endhaving its opposite edges serrated to form a rack and carried in looseengagement on its lever, said slot being adapted to admit of lateralindependent motion as regards lever and rack, a plurality of rack shoesadapted to engage with said rack having a restrictive sliding bearing onsaid lever on either side of said rack, said rack shoes being held incontact with the rack by means vof,.a .plurality of, pins andcatensionmember, said rack shoes when. actuated by said lever, be-

"ingladapted, to travelialong said rackto cause said rack tovary itsrelative position withv said lever to vary. the, effective length ofsaidconnector between said levers,

-17. Ina brake mechanism, the combination ofa plurality ofbrake shoesand levers :therefor, a connector, said connector being adapted, to.cause the brakeshoes to be. in close contact with the periphery of thewheels,.one end of. said connectorbeing pivoted to its lever, theremaining end being slottedand carried in loose engagementron.i-tsalever, said slotted portion having its opposite edges serrated toform a rack, rack shoes adapted to engage said rack and formed withflanges to facilitate their disengagement from said rack, said rackshoes being carried in loose engagement on either side of said rack bysaid lever, and said rack shoes when actuated by said lever, adapted tomove along said rack to vary the effective length of said connectorconnecting said levers, means for retaining the rack and shoes upon saidlever and assuring their contact, said means consisting of a pluralityof pins and a tension member, said pins being adapted to afford an evenbearing where held in contact with adjacent parts, one of said pinshaving a tapered portion.

18. In a brake mechanism, the combination of the actuating levers and aconnector therefor, said connector being provided at one end with a rackupon opposite surfaces, said rack being carried in loose engagement onone of said levers, rack shoes adapted to engage said rack and carriedin close contact on either side of said rack upon said lever, said rackand rack shoes being capable of independent lateral action as regardssaid lever, means for assuring close contact of said rack shoes andrack, means for disengaging said rack shoes from said rack, said meansconsisting of flanges formed integral with said rack shoes.

19. In a brake mechanism, the combination of the actuating levers, aconnector therefor and means whereby the distance between the levers maybe varied, said means consisting of a rack and rack shoes, means wherebythe rack and rack shoes are held in close contact, means whereby one ormore of said levers is caused to return to release position when brakingforce is withdrawn,

said rack shoes being provided with flanges or projections whereby theymay be disengaged from said racl 20. In a brake mechanism, thecombination of the actuating levers and a connector therefor, means foreliminating excess slack, said means consisting of a rack formed onopposite surfaces of one end of said connector and rack shoes adapted toengage 21. In a brake mechanism, the combination of the levers and aconnector therefor,

said levers being adapted to, when actuated by braking force, cause thebrake shoes to be in close contact with the periphery of the car wheels,said connector being provided with a rack on one end, rack shoes adaptedto engage such rack, said rack and Copies of this patent may be obtainedfor five cents each, by addressing the rack shoes carried in contact on,and capable of independent lateral action with reference to one of saidlevers, said lever being provided with a retractor whereby it is causedto assume original position when braking force is withdrawn.

In testimony whereof I afliX my signature in presence of two witnesses.

FRANK HORN.

Witnesses:

RICHARD B. CAVANAGH, JOHN H. EAGLESON.

Commissioner of Patents,

Washington, D. G.

